X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=lib%2Ftimeval.h;h=72cf49830de0b372f1a051aa525f7b5d6bacf7a3;hb=3444fdfb453d3593914cf1e18f9ac2f8b036e986;hp=5a7b6e25c62aeabc09b3b1089913446a828a8576;hpb=7a97619ae4484604c15b846ce7268094e048729a;p=sliver-openvswitch.git diff --git a/lib/timeval.h b/lib/timeval.h index 5a7b6e25c..72cf49830 100644 --- a/lib/timeval.h +++ b/lib/timeval.h @@ -1,5 +1,5 @@ /* - * Copyright (c) 2008, 2009, 2010, 2011, 2012 Nicira, Inc. + * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013 Nicira, Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. @@ -43,20 +43,14 @@ BUILD_ASSERT_DECL(TYPE_IS_SIGNED(time_t)); /* Interval between updates to the reported time, in ms. This should not be * adjusted much below 10 ms or so with the current implementation, or too * much time will be wasted in signal handlers and calls to clock_gettime(). */ -#define TIME_UPDATE_INTERVAL 100 +#define TIME_UPDATE_INTERVAL 25 -/* True on systems (particularly x86-64 Linux) where clock_gettime() is - * inexpensive. On these systems, we don't bother caching the current time. - * Instead, we consult clock_gettime() directly when needed. - * - * False on systems where clock_gettime() is relatively expensive. On these - * systems, we cache the current time and set up a periodic SIGALRM to remind - * us to update it. - * - * Also false on systems (e.g. ESX) that don't support setting up timers based - * on a monotonically increasing clock. */ +/* True on systems that support a monotonic clock. Compared to just getting + * the value of a variable, clock_gettime() is somewhat expensive, even on + * systems that try hard to optimize it (such as x86-64 Linux), so it's + * worthwhile to minimize calls via caching. */ #ifndef CACHE_TIME -#if defined ESX || (defined __x86_64__ && defined LINUX_DATAPATH) +#if defined ESX #define CACHE_TIME 0 #else #define CACHE_TIME 1